You do not have permissions to make this API call (again)

Hi,
I’ve set up a testing account in sandbox.paypal.com, and i did get my api username and password.
I entered the credentials in the Merchant Account settings in invoiceplane, selected Paypal Express and enabled Test mode.

I then created an invoice and went to Pay now but i keep getting this error.

You do not have permissions to make this API call

No matter what i try…i cant get the paypal testing to work.
Any help would be appreciated.

ps: Using the latest invoiceplane version.

this how I got that Fix

got you paypal account them your API

then in invoiceplane paypal express setting

API Username
API Password
API Signature

make sure that the test is off and everything just fine don’t you use the certificate API

@Jerry Could you please verify that @pedro’s fix is working?

Sorry for the delay, i was away on vacations.

Hmm i tried it but now i get error : "Security header is not valid "

I think i understood it correctly…I guess where @pedro says API Signature, means ‘Fingerprint’ in paypal ?